Tool to decrypt/encrypt DTMF codes. Dual-tone multi-frequency DTMF codes are combinations of sound frequencies used in phones when dialing numbers.
DTMF Code - dCode
Tag(s) : Telecom, Substitution Cipher
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DTMF Code
DTMF Frequencies Decoder
DTMF Frequencies Encoder
Answers to Questions (FAQ)
What are DTMF Codes? (Definition)
A DTMF code for dual-tone multi-frequency, is the name given to a combination of sound frequencies (beep) emitted by the keys of a telephone keypad.
The sounds emitted can be used by telephone servers, either to recognize a dialed number, or by automated voice servers to recognize which keys are typed by the user.
How to encrypt a number using DTMF Codes?
DTMF codes are used by phones and can be used to substitute numbers with their sound wave frequency as described in the table:
| 1209 Hz | 1336 Hz | 1477 Hz | 1633 Hz | |
| 697 Hz | 1 | 2 | 3 | A |
| 770 Hz | 4 | 5 | 6 | B |
| 852 Hz | 7 | 8 | 9 | C |
| 941 Hz | * | 0 | # | D |
Example: To crypt DC0D3, look for D which is the combination of 941Hz and 1633Hz, then write it 1633-941 (or 941-1633). The complete ciphered message is 1633-941/1633-852/1336-941/1633-941/1477-697
How to decrypt Codes DTMF cipher?
How to recognize DTMF Codes?
There are only 8 frequencies: 697 Hz, 770 Hz, 852 Hz, 941 Hz, 1209 Hz, 1336 Hz, 1477 Hz and 1633 Hz.
What does DTMF means?
DTMF stands for dual-tone multi-frequency and translates sometimes into Vocal Frequencies.
Source code
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